std::atomic is, for the most part, just a thin veneer on top of compiler
builtins. Hence, it should be available even when threads are not available
on the system, and in fact there has been requests for such support.
This patch:
- Moves __libcpp_thread_poll_with_backoff to its own header so it can
be used in <atomic> when threads are disabled.
- Adds a dummy backoff policy for atomic polling that doesn't know about
threads.
- Adjusts the <atomic> feature-test macros so they are provided even when
threads are disabled.
- Runs the <atomic> tests when threads are disabled.
rdar://77873569
Differential Revision: https://reviews.llvm.org/D114109
Since coroutine is merged in C++ standard and the support for coroutine
seems relatively stable. It's the time to move the implementation of
coroutine out of the experimental directory and the std::experimental
namespace. This patch creates header <coroutine> with conformed
implementation with C++ standard. To avoid breaking user's code too
fast, the <experimental/coroutine> header is remained. Note that
<experimental/coroutine> is deprecated and it would be removed in
LLVM15.
Reviewed By: Quuxplusone, ldionne
Differential Revision: https://reviews.llvm.org/D109433
This reverts part of commit b82683b2eb.
I hadn't intended to remove the `// -*- C++ -*-` comment line
from `libcxx/include/version`, only from the generated tests.
Thanks to Raul Tambre for the catch.
Even if these comments have a benefit in .h files (for editors that
care about language but can't be configured to treat .h as C++ code),
they certainly have no benefit for files with the .cpp extension.
Discussed in D110794.
All supported compilers implement __builtin_addressof. Even MSVC implements
addressof as a simple call to __builtin_addressof, so it would work if we
were to port libc++ to that compiler.
Differential Revision: https://reviews.llvm.org/D107905
All supported compilers have implemented __has_unique_object_representations
for a while, so it's reasonable to remove the workaround.
Differential Revision: https://reviews.llvm.org/D107834
All supported compilers have been supporting __is_aggregate for a long
time now, so it's reasonable to remove this workaround.
Differential Revision: https://reviews.llvm.org/D107833
All supported compilers should support
_LIBCPP_HAS_NO_BUILTIN_IS_CONSTANT_EVALUATED so this can be removed.
Reviewed By: ldionne, #libc, Quuxplusone
Differential Revision: https://reviews.llvm.org/D107239
This prevents std::format to be available until there's an ABI stable
version. (This only impacts the Apple platform.)
Depends on D102703
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D102705
This patch changes the variant even in pre-C++2b.
It should not break anything, only allow use cases that didn't work previously.
Notes:
`__as_variant` is used in `__visitation::__variant::__visit_alt`, but I haven't used it in `__visitation::__variant::__visit_alt_at`.
That's because it is used only in `__visit_value_at`, which in turn is always used on variant specializations (that's in comparison operators).
* https://wg21.link/P2162
Reviewed By: ldionne, #libc, Quuxplusone
Differential Revision: https://reviews.llvm.org/D97394
libc++ was previously a bit confused by what the value of __cpp_concepts
should be. Also replaces `__floating_point` with `floating_point` now
that it exists.
Differential Revision: https://reviews.llvm.org/D97015
Before this patch, feature-test macros didn't take special availability
markup into account, which means that feature-test macros can sometimes
appear to "lie". For example, if you compile in C++20 mode and target
macOS 10.13, the __cpp_lib_filesystem feature-test macro will be provided
even though the <filesystem> declarations are marked as unavailable.
This patch fixes that.
rdar://68142369
Differential Revision: https://reviews.llvm.org/D94983
This is the first step at implementing <format>. It adds the <format> header
and implements the `format_error`. class.
Implemnts parts of:
-P0645 Text Formatting
Reviewed By: ldionne, #libc, miscco, curdeius
Differential Revision: https://reviews.llvm.org/D92214
I accidentally disabled this feature-test macro in my D93830,
due to a rebasing conflict. It had been enabled by my D93815,
and should have remained enabled.
It's still a little confusing because in many cases C++17 and C++20
have different values, and libc++ implements the C++17 behavior but
not the C++20 behavior; 'unimplemented' can't represent that scenario.
Ultimately we probably ought to completely redesign the script to be
in terms of paper numbers, rather than language revisions, and make
it generate the CSV files like "Cxx2aStatusPaperStatus.csv" as well.
Most newly added macros are unimplemented. I've marked a few as implemented,
though, based on my reading of the code; for example I was pretty sure
`__cpp_lib_latch` is implemented since we have `<latch>`.
Differential Revision: https://reviews.llvm.org/D93830
Implements P1956: On the names of low-level bit manipulation functions.
Users may use older versions of libc++ or other standard libraries with the old names. In order to keep compatibility the old functions are kept, but marked as deprecated.
The patch also adds a new config macro `_LIBCPP_DEPRECATED_MSG`. Do you prefer a this is a separate patch?
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D90551
This commit adds std::construct_at, and marks various members of
std::allocator_traits and std::allocator as constexpr. It also adds
tests and turns the existing tests into hybrid constexpr/runtime tests.
Thanks to Richard Smith for initial work on this, and to Michael Park
for D69803, D69132 and D69134, which are superseded by this patch.
Differential Revision: https://reviews.llvm.org/D68364
Similar to <concepts>, we need to protect the header and test against
inclusion and being run if concepts aren't supported by the compiler.
Differential Revision: https://reviews.llvm.org/D82171
This commit adds missing support for constexpr in std::array under all
standard modes up to and including C++20. It also transforms the <array>
tests to check for constexpr-friendliness under the right standard modes.
Fixes https://llvm.org/PR40124
Fixes rdar://57522096
Supersedes https://reviews.llvm.org/D60666
Differential Revision: https://reviews.llvm.org/D80452
Summary:
As described in the bug report:
The commit a8b9f59e8caf378d56e8bfcecdb22184cdabf42d "Implement feature test macros using a script" added test features macros for libc++. Among others, it added `__cpp_lib_hardware_interference_size`. However, there is nothing like std::hardware_constructive_interference_size nor std::hardware_destructive_interference_size, that should be in header <new>.
* https://bugs.llvm.org/show_bug.cgi?id=41423
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D80431
Summary: The return type modification has already been implemented in rL364840 and rL365290.
Reviewers: ldionne, mclow.lists, EricWF, #libc!
Reviewed By: ldionne
Subscribers: christof, dexonsmith, libcxx-commits
Tags: #libc
Differential Revision: https://reviews.llvm.org/D70275